An example of a liquid crystal display device is disclosed in Patent Document 1. The liquid crystal display device disclosed in Patent Document 1 includes a liquid crystal panel, and a display backlight unit that supplies light to the liquid crystal panel. The display backlight unit includes a primary light source, a light guide plate that guides primary light emitted by the primary light source, and a QD film that contains quantum dot phosphors that are excited by the primary light traveling through the light guide plate and output secondary light.